U2F keys, such as the yubico YubiKey are relatively easy and inexpensive way to add two factor authentication to one’s workstation. Adding U2F authentication to local accounts on a linux machine is quite easy. In Gentoo/Funtoo, the pam_u2f ebuild will provide everything you need to get started.
In KDE 4, Konqueror has been replaced for the most part by Dolphin for all folder/directory viewing. However, by default Firefox will end up opening Konqueror if you right click on a downloaded item and select “Open Containing Folder”. It would be nice if Firefox would open the containing folder for downloads in Dolphin. There is a simple way of achieving this, and no command line work is required!